1. Field of the Invention
The present invention relates to building constructions and the like and, more particularly, to improved types of struts for space frame systems for providing an improved load carrying structural capacity and additional versatility in attaching conjunctive building components and systems.
2. Description of the Prior Art
The C. W. Attwood Pat. No. 3,270,478, C. W. Attwood et al U.S. Pat. No. 3,421,280, and H. V. Papayoti U.S. Pat. No. 3,443,348, all of common ownership with the present application, disclose a standardized system of space frame construction involving the use of lightweight, interchangeable elements of high quality material, manufactured to close tolerances, that can be assembled at a very low cost even by relatively inexperienced workers to form structures varying greatly in design and capable of being readily disassembled, altered, or expanded to meet the changing needs of the user, the components being almost completely salvageable to permit relocation and reuse. Such a flexible type of structural framework is well suited for many different types of buildings, pavilions, three dimensional trusses, structural spans and the like. In addition, such a structural framework meets not only requirements of flexibility, standardization and high quality, but is capable of carrying large loads and can be engineered to form space enclosures of various sizes and shapes instead of being limited to certain overall fixed dimensions as is the case with conventional structures.
As disclosed in the aforesaid patents, a space frame is a structure in which forces act in three or more directions in space. The structure uses four substantially standardized basic parts; namely, connection fixtures struts, bolts and nuts. The essence of the four basic parts is a preformed universal connecting fixture having horizontally and angularly oriented seats with accurate locating and securing means to which the struts are secured by the nuts and bolts. The space frame system can be applied in assembly roof span constructions as well as floors and other structures.
Until the appearance on the market of space frames, known by the trademarks "UNISTRUT" and "ATTWOOD SYSTEM," trusses and similar parts used in roofs, floors and other building structures were either welded together and carried in assemblies to the construction site or were assembled by welding, riveting or bolting in the field. Specified parts, which individually were adapted for only one specialized use, had to be altered as necessary as construction progressed. The shortcomings and inconveniences of prior construction systems have been overcome by the space frame system of construction utilizing lightweight, easily handled modular parts. Since these parts are manufactured in large quantities and are accurately dimensioned, the interchangeability of the parts is a considerable advantage. The precision with which parts are made in the factory insures speed and accuracy in assembly. The parts arrive on the site prefinished and are readily joined together. Workmen do not have to use tapes or squares and the simplicity of assembly even permits the employment of relatively unskilled labor.
Such space frame structures provide a building construction having a floor structure or a roof structure that is held at a predetermined distance above the ground and has appropriate load carrying capacity and characteristics. The struts must be of a design permitting attachment in a variety of positions so that they can readily be attached to support a roof or floor deck, ceiling panel, mechanical, electrical, air conditioning and other like distribution systems.